The truck in the subject line has been having overheating problems. It seems to drink coolant. No coolant leak can be found. The thermostat checks out ok. I am changing all of the drive belts today on the off chance that one of them loose and impairing pump function. I have always had a suspicion that the coolant return system was failing. But I really don't know how to diagnose that beyond checking the tube for leaks. There is a possiblity that the EGR is screwy but I had the impression that it failing is a pretty rare thing. I don't have a code checker. Any advice about this beast would be appreciated.
